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arXiv · 2105.00559

Correlated many-body noise and emergent $1/f$ behavior in an anharmonic fluctuator model

P N Thomas Lloyd·Valentin Walther·Hossein Sadeghpour
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Abstract

Fluctuating electric fields emanating from surfaces are a primary source of decoherence in trapped ion qubits. Here, we show that superradiant phonon-induced excitation exchange between adatoms can lead to a reduction of electric field noise at low temperatures. We derive an exact mapping between the noise spectrum of $N$ fluctuators with $M$ vibrational levels to $N+M-1 \choose N$-1 two-level dipoles. We provide conditions for which the ubiquitous $1/f$ noise can emerge, even though the system is composed of only a single type of fluctuator, thus suggesting a new mechanism for the phenomenon.

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P N Thomas Lloyd, Valentin Walther, Hossein Sadeghpour. 2021-05-02. Correlated many-body noise and emergent $1/f$ behavior in an anharmonic fluctuator model. https://doi.org/10.1103/physreva.105.l010402

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